If you can't sleep at night because you're paranoid about a stock market crash, buy some long dated put options on SPY to insure your portfolio or to hedge against the unknown. If you're scared about a bond market crash, buy long-dated put options on TLT instead. The reason for long-dated puts rather than short-dated puts has to do with lower theta decay. Options can be expensive so this is a short-term solution.
> If the dollar and the stock market are "going to crash"...
-The scenario in which that happens is when corporate profits are lower than expected and inflation is higher than expected.
The better solution is to not buy overvalued stock and underperformant corporations in the first place but a wise man once said: "Don't go into stock-picking until you know how to value a stock." If you don't know how to value a stock, then the solution is to go into real assets like real estate, gold, or commodities. If you prefer real estate, REITs with a low P/AFFO or P/FFO ratio will have better returns. If all of the corporations and REITs are overvalued, the textbook-solution is to start your own public corporation or REIT.
Last, don't put all of your eggs in one basket.